User equipment may operate in various modes in, for example, a UMTS telecommunications network. On initial turning on of user equipment in the cell, it will typically operate in “idle mode”. Once it synchronises and attaches itself to a base station, it gains radio resource control (RRC) connection and is referred to as being in connected mode. User equipment in idle mode does not have a radio resource control connection. If user equipment is RRC connected it can be in one of five different RRC states: Cell_DCH, Cell_FACH, enhanced Cell_FACH, Cell_PCH, or URA_PCH states.
User equipment typically moves into Cell_DCH state when its data traffic is high. In a Cell_DCH state, the user equipment is allocated a dedicated channel on which to transmit and receive data from a base station. In a network operating according to typical UMTS architecture, user equipment can be in a Cell_DCH state when it is expected to have a high volume of traffic. Operation in a Cell_DCH state is typically highly demanding of battery power
It will be appreciated that for data traffic which is particularly bursty in nature, operation in a full Cell_DCH state can be particularly wasteful of battery at user equipment and also of available radio resource. Thus, the ability to handle bursty traffic without entering a more dedicated state is beneficial to overall network operation.
The widespread popularity of “smartphones” in commercial networks has led to a change in typical data traffic profile carried within a network. The loading of Web pages and subsequent user reading, for example, has led to a data traffic profile which has become substantially discontinuous or bursty and traditional communication link establishment techniques and transfer techniques designed primarily for continuous data transmission may not offer a particularly efficient or prompt means to handle bursty traffic.
User equipment may be operable, when not in a Cell_DCH state, to use a random access channel (RACH) on the uplink and a base station will operate to communicate with user equipment using a forward access channel (FACH). RACH and FACH have a small data carrying ability and in WCDMA or UMTS systems it is possible for user equipment and base stations to operate and communicate data traffic therebetween using shared or common resources on downlink and uplink when user equipment is operating in non-Cell_DCH RRC states.
Those non-Cell_DCH states typically use common channels, and thus there is limited resource available within a cell to support communication between user equipment and a base station on those shared channels. Aspects described herein offer methods of utilising available common channels to allow signalling and data traffic transfer without utilising a full Cell_DCH RRC state.